Arsene Wenger believes Arsenal still have automatic Champions League qualification in their own hands despite the disappointment of Swansea's 1-0 smash-and-grab raid at the Emirates Stadium last night.

The Gunners were aiming to keep up pressure on Manchester City in the battle for second place in the Barclays Premier League, and also to stay ahead of Manchester United, whom they face on Sunday.

However, despite creating enough chances to win the match during a one-sided second half, Arsenal failed to find away past former goalkeeper Lukasz Fabianski via a combination of some poor finishing and some decent reflex stops from the Pole who left the club in the summer.

Arsenal's shortcomings in attack were punished when substitute Bafetimbi Gomis headed in a late winner on 86 minutes, which was given via the Goal Decision System after David Ospina looked to have clawed the ball off the line.

The defeat means Arsenal missed the chance to move level on points with City.

While the Gunners still hold a game in hand over both sides surrounding them, they would fall below United and down to fourth with defeat at Old Trafford on Sunday.

"It is very important to finish in the top three," said manager Wenger, whose side had to again come through a stressful Champions League qualifier at the start of this season.

"We still have a game in hand. What is crucial is to respond on Sunday and show that it (Swansea) was an accident today. That is the most important thing."

Arsenal had nine shots on target, while Swansea scored from one of just three having spent most of the second half on the back foot.

"We were unlucky I think against a team who refused to play completely and just defended," said Wenger, whose side had not lost at the Emirates Stadium in the league since defeat by United on November 22.

"In the last two home games we didn't score and that was frustrating when you have so much of the ball and play with such accuracy around the box.

"They came just to defend with four defenders and six midfielders, and they defended. That's it.

"If you win, you are fantastic, but if you lose people say to you, 'why did you not play?'. They won so they are fantastic."

Olivier Giroud, Theo Walcott, Aaron Ramsey and Alexis Sanchez all squandered opportunities with only Fabianski to beat.

Wenger said: "We rushed our finishing. Sometimes we were maybe too eager to finish alone rather than passing the ball.

"Fabianski did well, but I believe also on some occasions we made it too easy for him."

Swansea's victory was their third in a row in the league, and perfect preparation for the weekend visit of City.

Manager Garry Monk had no issues with his side's game plan.

"We could have come here and gone toe to toe, but with the individual quality that Arsenal have, they could have maybe hurt us," he said.

"The idea was to get to the last 20 minutes still in the game, make the substitutions and hope we could get the goal on the breakaway, which proved to be the case.

"If we didn't play, I don't know how we got three points."

Swansea are still eighth, but closed the gap on the Europa League qualification spots with sixth-placed Tottenham now only two points ahead and Southampton one.

Should Arsenal go on to win the FA Cup, then seventh spot in the league would earn a place in Europe's much-maligned second-tier competition.

"What will be will be, but I don't lie in bed at night worrying about it," said Monk.

"The only thing that will change if we get there will be the planning in terms of recruitment in the summer, not that the chairman will want to hear that."

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